Persistent Diatoms in Mature Tanks & GDA

[JohnC]

Alas it looked it's best back then and plant health has been declining for the reasons above since that time. In various tanks at certain times.

 

[G H Nelson]

Lovely Aquascaping room John

 

[JohnC]

Lovely Aquascaping room John

Thanks man,

Alas it now makes me somewhat sad going in there. Hopefully soon i'll perk up a bit. I'm going to shift to emersed growth and riparium set ups for a change. Hopefully the lower energy/plant mass in the water and associated water column dosing will not recreate the same diatom and GDA issues.

I need a break from high tech hassles. :/

 

[alto]

The setups are using Kessil 160's that are dialed down

I use these lights on my 53cm tall tanks, and always run full on, with no visible algae

Don’t forget that when you decrease the intensity on these lights (while the driver tech maintains spectra) the “cone” of lightfall diminishes significantly

Scaperoom is astounding

 

[Bryce]

Beautiful studio!! My hunch is lighting.. your tanks appear to be sparse in plants, heavy on the hard scape and that’s your style. I would back way back off the lights some, Crank up co2, or add more plants. This style is a tough one to balance. My 2 cents

 

[JohnC]

I use these lights on my 53cm tall tanks, and always run full on, with no visible algae

Don’t forget that when you decrease the intensity on these lights (while the driver tech maintains spectra) the “cone” of lightfall diminishes significantly

Scaperoom is astounding

Indeed. They are mounted deliberately higher and then dialled down. With the PAR meter used to check for dark spots.

Beautiful studio!! My hunch is lighting.. your tanks appear to be sparse in plants, heavy on the hard scape and that’s your style. I would back way back off the lights some, Crank up co2, or add more plants. This style is a tough one to balance. My 2 cents

Thanks man,
It is actually only that single tank that is hardscape heavy which also runs pretty low light and lean ferts.

The rest of 90 - 100% planted.

I've leaned away from doing iwagumi as i have too much to maintain tbh.

 

[G H Nelson]

Hi John
Out of interest what is the Ph of the spring water?
hoggie

 

[JohnC]

about 6.4 but no natural hardness.

i reminerlize with TNC GH booster and seachem alkaline buffer for KH. Aiming for 5 dGH and about 3 dKH currently. Although that was all over the place a few months back.

 

[G H Nelson]

Have a look at the below link...interesting!
https://www.plantedtank.net/forums/23-algae/374505-green-dust-algae-i-think-i-found-cure.html
hoggie

 

[JohnC]

Have a look at the below link...interesting!
https://www.plantedtank.net/forums/23-algae/374505-green-dust-algae-i-think-i-found-cure.html
hoggie

I think i've skim read this one and chatted to Tom B about it before.

This does ring true -

". i also discovered low PH water is Prone to GDA when using EI dosing, why? because when using KNO3, Bacteria have to convert NO3 back to NH4 for the plants, plants are normally covered with Bacteria who convert this, but in low PH water Bacteria aren't very active. this might explain why some people have problem when dosing EI and using very low PH. now on the other side EI worked very well in high PH water, keep in mind high PH water is beneficial for Bacteria and they are most active under these conditions."

And partly why i've been drilling down into the kH and ph stability of the tanks. Before i addressed the kH issue I was getting a fair amount of random crypt melting in a couple of tanks which has now stopped. I was trying to drill down into the kH buffering capacities of the aquasoils as things did decline a fair bit once the soils aged. But that could be co-incidence, but also could indicate the plants were taking NH4 from the soils and when that declined the NO3 issue described by Happi above kicked in more.

I'll keep reading (page 3).

 

[JohnC]

Certainly the amount of GDA that occurs is almost directly proportional to the level of fert dosing (ie NO3) but obviously in my case this is also somewhat dictated by the energy and fert needs of each tank.

 

[JohnC]

Alas i do enjoy Happi's posts but this must have been early on in his scaping.... by page 4 he's recounted (been corrected on APF) the idea that NO3 is converted to NH4 by bacteria that are not present enough in low ph tanks. Thought that sounded a little bit too elegant.

Certainly think my low kH and ph is/was causing issues. Still having said issues now i've resolved that thou.

edit - how having read through it all it's not the post i'd like it to be..... i've done so much reading on this issue now and nothing really strikes home.

i wish Happi's test 3 with urea he'd actually kept the rest of the variables the same rather then adding in extra Ca Mg too.....

there is a reason after all my reading i drilled down into the lower ph and kH issues to fix. i'm hopefully going to break my GDA outbreak chains with my current treatments. I'd love the diatoms to be nailed too.....

Similarly thou, lack of bacteria due to lower ph and ammonia/cycling happening on a weekly basis could be a thing.

 

[alto]

There’s a lot of meandering on forums where conclusions (cause/effect) are drawn regarding various parameters

I run my tanks at my tap water parameters, KH, GH very low (it’s basically rain water/snow melt that collects in a ground reservoir (and can get a bit peat stained during storms)) pH 6ish, 22-26C, adding Tropica fertilizers - except when I don’t - and using Tropica soils the last while
(nutrient enriched base layers such as Sera Flore Depot beneath fine gravels previously)

I tend to keep fish from very soft water areas so I don’t add KH and GH, I add low to moderate CO2 (again depending upon fish comfort)
I often have significant ambient light and even direct (morning) sunlight on tanks - fish are meant for sunlight viewing

Tanks run with minimal algae, occasional diatoms during startup (I’m surprised when it happens, despite fluctuating CO2 (especially when I run out and don’t replace for a few days 😳), rather erratic care (my intentions are good) ...
Recently I’ve let my kitchen nano run wild: CO2 ran out early December, no fertilizers, water’s only been topped up since, some plants have receded and disappeared (the Eriocaulan ‘polaris’), others have become a jungle, photoperiod has not changed as that is programmed into the light - it’s been an interesting experiment in neglect - and still, no visible algae
(Note there’s a few snails and odd shrimp I still occasionally see)

Similarly thou, lack of bacteria due to lower ph and ammonia/cycling happening on a weekly basis could be a thing.

While possible, this seems unlikely - does your pH drop to 4?
The science of aquarium nitrogen cycle has changed significantly in recent years, Darrel has provided some decent links (just the first post in that thread is pretty convincing 🙂)

 

[JohnC]

There’s a lot of meandering on forums where conclusions (cause/effect) are drawn regarding various parameters

I run my tanks at my tap water parameters, KH, GH very low (it’s basically rain water/snow melt that collects in a ground reservoir (and can get a bit peat stained during storms)) pH 6ish, 22-26C, adding Tropica fertilizers - except when I don’t - and using Tropica soils the last while
(nutrient enriched base layers such as Sera Flore Depot beneath fine gravels previously)

I tend to keep fish from very soft water areas so I don’t add KH and GH, I add low to moderate CO2 (again depending upon fish comfort)
I often have significant ambient light and even direct (morning) sunlight on tanks - fish are meant for sunlight viewing

Tanks run with minimal algae, occasional diatoms during startup (I’m surprised when it happens, despite fluctuating CO2 (especially when I run out and don’t replace for a few days 😳), rather erratic care (my intentions are good) ...
Recently I’ve let my kitchen nano run wild: CO2 ran out early December, no fertilizers, water’s only been topped up since, some plants have receded and disappeared (the Eriocaulan ‘polaris’), others have become a jungle, photoperiod has not changed as that is programmed into the light - it’s been an interesting experiment in neglect - and still, no visible algae
(Note there’s a few snails and odd shrimp I still occasionally see)



While possible, this seems unlikely - does your pH drop to 4?
The science of aquarium nitrogen cycle has changed significantly in recent years, Darrel has provided some decent links (just the first post in that thread is pretty convincing 🙂)

The ph of 4 ish was recorded on a blackwater breeding project I did for Rocket Panchanx last year. I don't recall any test strip tests showing that low ph in the main room however. I do admit that i wasn't obsessively testing stuff until the last 6 months while trying to get to the bottom of stuff. mostly it came out 6ish.

I also prefer to keep things lower kh and gh generally and i think i'm going to head the way of the "duckweed index" and shrimp/odd ball keeping and emmersed/riparium growth i think i'll try and keep as much of the nutrients in the substrate as possible.

i always thought when i moved here that the spring water was going to be superb for fishkeeping but really i've never had great growth here compared to Edinburgh.

 

[alto]

It’s possible there are some trace nutrients in your spring water which aren’t “trace”, this can cause problems in very soft acidic water (where it may be less significant in harder or more alkaline water, re bioavailability and chemical availability is often affected by these parameters)

Obviously something is amiss in your tanks, and it would be nice to be able to pinpoint something but even if you had substrates and water extensively tested (analytical labs), there might still only be suggestions and nothing conclusive

I’d consider having the spring water analyzed (get a list of exactly what’s going to be tested and costs before going ahead) but also look at your delivery or storage system

Consider any tank additives (fertilizers, GH/KH etc), also any possible aerosols in the room (though this seems unlikely as I’d expect livestock to be affected before plants)

I experience minimal algae in my tanks, but I also realize that growth could be faster if I adjusted GH/KH, added more fertilizers etc (I prefer Filipe Oliveira and Jurijs mit JS style of plant growth, where I can trim monthly rather than weekly)
There are also some “easy” plants that do poorly under my tank conditions, while some “difficult” plants thrive even with minimal care (I used to put in rather more effort 😉)
I set up a 60P last February, and the Elatine hydropiper invaded the hair grass and MC ... until temperatures went up (sudden early summer heat and tank was in a upper level room that was very warm by 10am)

 

[JohnC]

I've actually got some analysis done for the water due to the potential of lead and copper in the supply in the community hall near by. We are on the same bit of the supply.

The lab tests there were pretty scary but at the same time really only represented the addition of metals from the internal pipes in that hall and their run from the plastic at the stop cock. Once you run it for a bit it runs clear. Similarly we have some older pipes here but it runs clear faster and we have had our internal house stuff done.

The sheds supply feeds off before the internal house stop cock so i did chase around the idea with Tom Barr and Denis that the plants might be suffering from Copper, lead or zinc toxcity from accumulated buildup (the initial hall readings from the lab tests were off the chart). But when i actually went out and bought a aquarium copper testing kit for my tanks I discovered that my house supply was ok'ish. Less than 1ppm when first run in the morning, quickly declining to almost zero. The shed was the same, some copper on the first run of the tap but decling to zero once it ran for a bit.

Additionally the water is stored in two header tanks in the fish room office so a copper test on the feeds from that also showed zero/almost zero. Plus the shrimp are all fine.

So...... not that.....

As i say i've been chasing this one around for a long while.

I did spend a bit of time changing the water in one tank with water from my dehumidifer and I have to say things were the same if not worse in that tank for that period.

 

[JohnC]

From the hall.



Now i can actually get my supply tested for free as part of a scottish government scheme to improve private supplies to aim to get a grant to fit an acid neutraliser.

But really i don't expect ours to be anywhere as high in copper/lead/zinc as the halls next door in the woods. Since our property was upgraded from a train station to a private house in the 70's and has had extensive plumbing work done in the last 40 years.

 

[alto]

I did spend a bit of time changing the water in one tank with water from my dehumidifer and I have to say things were the same if not worse in that tank for that period.

Most dehumidifier water does not test well - I don’t know where/how this methodology developed
(Sorry I rarely bookmark links, and this is stuff I looked up ages ago when I first read of people using dehumidifier water in their aquariums)

There are other possibilities than copper, but I’m somewhat sceptical that this is really the track worth pursuing

If you’re up for it,
1) remove and save plants from any given tank, ditch the substrate, rinse the filter media thoroughly (discarding any sponges or sand (should you happen to have a sand filter 😉)), rescape with new aquarium soil (whatever brand you prefer), replant and see what happens
2) as above, but just deep clean the substrate (Filipe Oliveira style), rescape, replant etc
3) as above (2) but now include Filipe Oliveira style Seachem Flourish Tabs (I believe FO also uses AquaRio plant tabs in another scape, includes details etc)
4) remove plants, superficially clean substrate, filter media etc, replant with newly purchased plants (just choose something that usually does well for you and lower cost)

On all tanks, follow usual new setup protocols, frequent water changes, lean water column dosing (want to see what’s happening in the substrate) etc

 

[alto]

Re plant health, you might find this interesting

https://iwaponline.com/wqrj/article/7/1/59/39948/Cadmium-and-Zinc-Toxicity-and-Synergism-to

(an older article but open access 😉)

https://www.academia.edu/2008284/Metal_toxicity_and_tolerance_in_plants
not aquatic plants, but symptoms of toxicity may be of interest (obviously sensitive may vary across plants species, not just across aquatic vs non-aquatic species)

https://www.researchgate.net/public..._an_Aquatic_Macrophyte_Ipomoea_Aquatica_Forsk
newer but also quite high levels of zinc (but also short term study)

This is from a quick (5 min) search so likely rather more pertinent studies can be found

 

[JohnC]

yeah i went through the stuff on metal toxicity while narrowing down that as an option but as i mentioned the testing of the water for the room actually didn't show the same silly readings from the hall.

i've done 2 and 4 of your list 🙂